Today's motor vehicles offer a multitude of safety, comfort and information functions. To that end, the motor vehicles usually have various actuators and sensors. A control unit in the motor vehicle is used, for example, to pick up and process signals from the sensors, as well as to output control signals to the actuators. With an increase of functions intended to be offered in a motor vehicle comes also an increase in the demands on the control unit that controls these functions. In particular, a number of electric lines needed, with whose aid data and signals may be exchanged between the control unit and sensors or actuators, increases as well. For example, today's control units already have up to 200 electrical data lines and signal lines. Often, several lines are combined to form one wiring harness so as, for example, to permit the exchange of data between the control unit and a further unit already providing a function.
In order, for instance, to be able to service or repair the control unit, the lines are generally not connected permanently to the control unit, but rather are releasably attached to the control unit via a plug connection. Provided on the control unit for that purpose is a plurality of contact elements, e.g., in the form of plug pins or sockets, which are wired up in the interior of the control unit to corresponding signal lines and data lines to, e.g., control components or data-processing components of the control unit. These contact elements are able to cooperate with complementary mating contact elements that are provided in a connector, e.g., at the end of a wiring harness. The connector is plugged releasably into suitable receptacles on the control unit to thus produce an electrically conductive connection between the lines of the wiring harness and the associated contact elements of the control unit.
It has been observed that for control units which provide a very great number of contact elements for, e.g., up to 200 or more electric lines, it may be difficult to position the contact elements on the control unit with sufficient exactitude. Therefore, it was proposed in DE 10 2011 006 195 A1, for example, to provide a control unit with a modular electrical connector assembly, in which a plurality of connector modules are disposed side-by-side in a module carrier. In this case, each of the connector modules may be produced separately and with high precision. To produce the connector modules, in particular, injection-molding technologies may be used which, although permitting sufficiently high precision in the case of small assemblies, for very large units for connectors having, e.g., 200 contact elements, are often encumbered with a warpage and inadequate positioning precision resulting from that. In putting the connector assembly together, the various connector modules may be placed with suitable precision in relation to the module carrier, and only then be joined mechanically to the module carrier.